You count the pulses if your pulses feed the FTM 'external clock' input (CLKS = 0b11, and as selected in SOPT4). The CAPTURE function gives you a way to strobe the beginning and/or end instants that a software interrupt can then read and calculate the difference. As for speed, I can say that feeding the FTM in quadrature mode I can run up to 66% of the bus-clock speed. However, the external-clock goes thru an extra 'synchronizer' block in the block-diagram, so I wouldn't be surprised to see that a 60MHz bus-clock is indeed limiting to a 15MHz count rate.

You should be able to count at a max speed of 30MHz (system clk / 4 = 120MHz/4 = 30MHz); I have seen applications running the FTM at 24MHz. You can configure the FTM to generate an overflow interrupt when the count reaches your threshold value if the count is going up, if the ocunt is going down the interrupt could be generated when the count reaches 0.

You count the pulses if your pulses feed the FTM 'external clock' input (CLKS = 0b11, and as selected in SOPT4). The CAPTURE function gives you a way to strobe the beginning and/or end instants that a software interrupt can then read and calculate the difference. As for speed, I can say that feeding the FTM in quadrature mode I can run up to 66% of the bus-clock speed. However, the external-clock goes thru an extra 'synchronizer' block in the block-diagram, so I wouldn't be surprised to see that a 60MHz bus-clock is indeed limiting to a 15MHz count rate.

Thanks Earl, even I thought of feed the timer with the external clock , but unfortunately in the FRDM - K64F this input is not available , then I can do this test only once I have the MCU. If I try this, I will say you if all works.